I have a 2003 Chevy trailblazer loaded. My battery recently died so I bought a new one. But once I replaced it, my car ran fine. But my heat, and a/c blows, but it's a very little blow. Why doesn't my vents blow hard like they used to before my battery died? I already pulled and done steps with the Hvac fuse #36. That didn't work either.
My car has 100000 miles.
My car has an automatic transmission.
Hi there. This is a common occurrence on this vehicle after a loss of battery power. In some cases, you have to do the power reset several times for the programming to relearn itself. I would remove the same fuse again and then disconnect both battery cables. With them disconnected, touch them together and then reinstall the fuse. Then reinstall the positive battery cable followed by the negative cable.
If that still does not work, then I typically need to reprogram the HVAC module with a scan tool. In rare cases, the loss of voltage will damage the module. If the programming does not work then the module will need to be replaced. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your air conditioning/heating vents, and make any repairs that are needed.
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